The ventilation of drives exceeding 50 m length to be such as to dilute the nitrous fumes produced by blasting to . . . . . . . . and CO to . . . . . . . . within a period of . . . . . . . . min in long tunnel.
A. 5 ppm, 50 ppm, 5
B. 1 ppm, 25 ppm, 10
C. 10 ppm, 40 ppm, 2
D. 5 ppm, 40 ppm, 5
Answer: Option A
Related Questions on Drilling and Blasting
Which of the following prime characteristic the nonel blasting has?
A. It has greater shock to the surrounding
B. It is noiseless in character
C. It has tremendous effect on explosive column
D. It can not be used in a place where there is a chance of stray current
A. Fire, Explosion
B. Gas, Outburt
C. Rockburst, bump
D. None
Cyclone, bag filter and scrubber can be used for control.
A. Water pollution
B. Soil pollution
C. Air pollution
D. Noise pollution
A two phase system in which an inner or dispersed phase is distributed in an outer called
A. Emulsion
B. Slurry
C. Explosion
D. Erosion

Join The Discussion